In a store such as a convenience store, a monitoring system in which a camera that images an inside of the store is installed and a state of the inside of the store is monitored by using a video of the camera has been widely used. If an activity state of a customer within the store is able to be recognized by using the video of the camera, improvement measures of a merchandise display method within the store are prepared based on the activity state of the customer, and thus, it is possible to improve the sales and profits of the store.
In the related art, a technology that acquires information related to the activity state of the person in the monitoring area from videos of a plurality of cameras and generates an activity map acquired by visualizing the activity state has been known as a technology related to an analysis of an activity state of a person in a monitoring area (see PTL 1). In this technology, the activity map is illustrated with contour lines corresponding to activity levels of persons through color coding, and is displayed in the layout of the monitoring area so as to be superimposed thereon. A technology in which the monitoring area is divided into a plurality of blocks and a stay extent of the person is detected for every block has been known (see PTL 2). In this technology, a value (score) indicating the stay extent of the person is output for every block.